Echoing a University of Chicago study showing that children with sleep apnea are at risk for brain damage, researchers in the Netherlands have shown a link between childhood sleep disturbances and smaller gray matter volumes.

Their study was published in Sleep.

Desana Kocevska, MD, MSc, of Erasmus University in Rotterdam and colleagues used T1-weighted MRI to assess brain structure in 720 7-year-olds whose mothers had reported sleep disturbances. The scans were performed at regular intervals between 2 months and 6 years of age.

The team used linear regressions to test associations of sleep disturbances at each age, as well as sleep disturbance trajectories, with brain volumes. They recorded total brain volume, cortical and subcortical gray matter, and white matter.

The researchers found that sleep disturbances followed a declining trend from toddlerhood onwards.

Infant sleep was not associated with brain morphology at age 7; however, per sleep disturbance involving one frequent symptom or two less frequent symptoms at 2 and 3 years of age, children had significantly smaller gray matter volumes.

Further, sleep disturbances at age 6 years were associated with global brain morphology (gray matter: -7.3 [-12.1 to -2.6]; p value = .01).

“Consistently, trajectory analyses showed that more adverse developmental course of childhood sleep disturbances are associated with smaller gray matter volumes and thinner dorsolateral prefrontal cortex,” Kocevska et al. write.

Sleep disturbances from age 2 years onwards “are associated with smaller gray matter volumes,” they conclude. “Thinner prefrontal cortex in children with adverse sleep disturbance trajectories may reflect effects of sleep disturbances on brain maturation.”